Rate Comparison of the Maillard Reaction Between Milk Proteins and Human Milk Oligosaccharide

The Maillard reactions during dairy processing significantly affect both nutritional quality and product browning. However, the reactivity differences between human milk oligosaccharides (HMOs) and milk proteins remain unclear-a critical knowledge gap in optimizing infant formula production. This study systematically investigated the reaction kinetics of two structurally distinct HMOs (2'-fucosyllactose and lacto-N-neotetraose) with three major milk proteins (α-lactalbumin, β-lactoglobulin, and β-casein). Combining multiple methods, including furosine quantification, browning degree, SDS-PAGE, and free amino groups, it was found that 2'-fucosyllactose produced 1.3 times more Maillard reaction products than lacto-N-neotetraose, while α-lactalbumin exhibited the earliest glycation among the tested proteins. Kinetic modeling further established a reactivity hierarchy: 2'-fucosyllactose > lacto-N-neotetraose for HMOs and α-lactalbumin > β-lactoglobulin > β-casein for proteins. These findings provide the first comparative kinetic framework for HMO-milk protein interactions, providing specific optimization targets for dairy processing to minimize nutrient losses while controlling browning during infant formula production.